CWEweakness
CWE-1096 Singleton Class Instance Creation without Proper Locking or Synchronization
- Abstraction
- Variant
- Structure
- Simple
- Status
- Incomplete
- Languages
- Not Language-Specific
- CWE version
- 5.0
Description
The product implements a Singleton design pattern but does not use appropriate locking or other synchronization mechanism to ensure that the singleton class is only instantiated once.
Common consequences
• Other: Reduce Reliability — This issue can prevent the product from running reliably, e.g. by making the instantiation process non-thread-safe and introducing deadlock (CWE-833) or livelock conditions. If the relevant code is reachable by an attacker, then this reliability problem might introduce a vulnerability.
Detection methods
• Automated Static Analysis: Automated static analysis, commonly referred to as Static Application Security Testing (SAST), can find some instances of this weakness by analyzing source code (or binary/compiled code) without having to execute it. Typically, this is done by building a model of data flow and control flow, then searching for potentially-vulnerable patterns that connect "sources" (origins of input) with "sinks" (destinations where the data interacts with external components, a lower layer such as the OS, etc.)